Electric contact brush and connector



May 1941- K. cs. MARTIN 2,242,014

ELECTRIC CONTACT BRUSH AND CONNECTOR Filed Jan. 20. 1959 Inventor: Kenneth G. Martin,

His Attorney Patented May 13, 1941 ELECTRIC CONTACT BRUSH AND CONNECTOR Kenneth G. Martin,

to General New York Schenectady, N. Y., assignor Electric Company, a corporation of Application January 20, 1939, Serial No. 251,9s9

9Claims- My invention relates to an electric contact brush and connector and a method of making the same.

An object of my invention is to provide an improved and simplified contact ,brush and connector.

Another object of my invention is to provide an improved connector for an electric contact brush.

A further object of my invention is to provide an improved method of making an electric contact brush and connector.

Further objects and advantages of my invention will become apparent and my invention will be better understood from the following description referring to the accompanying drawing, and

v the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In the drawing, Fig. 1 is a side elevational view of an electric contact brush and flexible connector embodying myinventio Fig. 2 is a side elevational view of the brush shown in Fig. 1 with a part of the connectbr broken away; Fig. 3 is an enlarged view of a flexible connector and brush clip such as that shown in Fig. 1 with part of the clip broken away to illustrate better the manner in which the flexible conductor is secured to the clip; and Fig. 4 is a sectional view taken along line 4-4 of Fig. 3.

Referring to the drawing, I have shown a carbon electric contact brush ll, such as that used with commute-ting dynamo-electric machines, provided with a connector of my improved construction. This connector comprises a substantially V-shaped terminal clip ll, made of any suitable conducting material, to which a flexible stranded electrical conductor i2 is secured. In the past, it has been found that in securing such a flexible conductor to brush terminal clips, the strands of the conductor are embrittled by soldering to the clip or by fusing by the heat of a flame to such a terminal. In order to overcome this dimculty, I secure together the ends of a loop of flexible conductor I! by clamping them together in a terminal I! and arrange the closed portion of the loop so that a predetermined length of the conductor is in contact with the inner surface of the apex ll of the clip Ii. As shown in Fig. 3, the flexible conductor is spot welded at I! intermediate the ends of the portion of the loop in contact with the clip so that less than the predetermined length of conductor in contact with the clip becomes hardened and welded to the clip ii. In this manner. only the intermediate spot welded portion of the flexible conductor becomes hardened and a small portion it adjacent each end of the clip within the apex thereof remains flexible. In this spot welding operation, no flux is used, and therefore, no embrittlement of the conductor is produced by penetration of flux into the conductor between the strands thereof.

This spot welding is done by pressing an electrode against the portion l5 of the flexible conductor l2 and against the outer side of the apex ll of the clip ii, and then passing an electric current between these two electrodes. The brush connector is then applied to the carbon brush Ill, and one side of the clip ii is arranged in a slot ll in one side of the brush adjacent an end thereof, so that the loop I! of the flexible conductor I2 is in contact with the upper edge It of the brush Ill and provides an electrical contact therewith. The connector is secured to the brush ill by a hollow rivet l9 which extends through an opening in the brush and a complementary opening 2| in one side of the clip ii. In this manner, I provide a simplified brush and connector and method of making the same, wherein the portion of the flexible conductor which connects the brush terminal clip to the brush holder terminal is not embrittled adjacent the terminal clip by the method of securing it to this clip, and the useful life of the brush is increased by insuring the flexibility of this conductor, and

thereby. reducing the possibility of breakage of the conductor at the point where it is secured to the brush terminal clip.

While I have illustrated and described a particular embodiment of my invention, modifications thereof will occur to those skilled in the art. I desire it to be undertsood, therefore, that my invention is not to be limited to the particular arrangement disclosed, and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

What I claim as new, and desire to secure by Letters Patent of the United States, is:

1. An electric contact brush having a terminal clip secured thereto, and a flexible electrical conductor arranged in contact with and secured to said clip by a spot weld for a length thereof less than the width of said clip.

2. An electric brush having a V-shaped terminal clip secured thereto, and a flexible electrical conductor secured to said clip by a weld within the apex of said. clip.

3. An electric contact brush having a V-shaped terminal clip secured thereto, a flexible electrical conductor formed as a loop inserted between said clip and said brush. and a weld securing said conductor loop within the apex oi said clip.

4. An electric contact brush having a terminal clip secured thereto, a flexible electrical conconductor arranged in electrical contact with said clip for a predetermined length thereof and secured thereto for less than said predetermined length by a spot weld intermediate the ends of said predetermined length of conductor.

7. An electric contact brush having a terminal clip secured thereto, a flexible electrical conductor formed as a loop with a predetermined length thereo! inserted between said clip and said brush, and a spot weld securing said conductor loop to said clip intermediate the ends of said predetermined length of conductor.

8. An electric contact brush having a terminal clip secured thereto, a flexible electrical conductor formed as a loop with a predetermined length thereof inserted between said clip and said brush, and a spot weld for less than said predetermined length of conductor securing said conductor loop to said clip.

9. An electrical connector for a carbon brush or the like including an electrically conductive clip, a flexible electrical conductor having a predetermined iength thereof arranged in electrical contact with said clip, and a spot weld intermediate the ends of said predetermined length securing said flexible conductor to said clip.

KENNETH G. MARTIN. 

